ShowModal and MessageDlg, I have disabled form

[mmurgas]

Dear, it happens when opening a Form ShowModal and then create a MessageDlg message, I have the completed form disabled on some occasions, at what should it be?

 

example

Open form
FormXXX.Showmodal;
-
-
-
MessageDlg ('? Save info?', MtConfirmation, mbYesNo, OkSave);

...
completed form disabled

Thanks in advance for your help

 

mmurgas